In recent years, solar cells demand rises in various fields.
Due to their complex constitution, the solar cells have heretofore been manually fabricated. In order to improve the productivity, conveyer lines have now been proposed making it possible to automatically assemble the solar cells.
According, to JP-A-2001-223382, for example, a metal plate and a terminal box are automatically attached to a solar cell panel by executing a double-sided tape-sticking step in which the solar cell panel is placed on a conveyer, double-sided tape is stuck to the back surface of the solar cell panel, and a backing paper is peeled off; an adhesive-applying step of applying adhesive to the back surface of the solar cell panel; a metal plate-fixing step of fixing a metal plate to the back surface of the solar cell panel; a step of sticking double-sided tape to a portion of the metal plate on where a terminal box is to be mounted and peeling backing paper; a terminal box-fixing step of feeding a terminal box onto the metal plate to electrically connect it to the solar cell panel; and a potting material-filling step of feeding a potting material into the terminal box so as to be filled therein.
Further, a solar cell module of a wire collector system has been proposed in to which a photosensitive semiconductor film is formed on each of the solar cells that constitute the solar cell module and many collector wires are arranged thereon in parallel.
The solar cell module is constituted by solar cells which are connected together in a suitable number of pieces.
That is, the solar cell module is produced through the steps of feeding the solar cells, connecting the solar cells together, connecting diodes thereto, sealing the front and back surfaces, checking the electric conduction and inspection.
An SUS plate of a predetermined size is used for the cells from which the solar cell module is constituted through the above-mentioned steps, so that when a plurality of solar cells are connected together, a predetermined gap (e.g., 1 to 1.2 mm) is maintained among the cells.
The assembly line employs conveyers constituted by attaching magnets to steel belts, and the solar cells are conveyed attracted by the magnets. The solar cells are intermittently fed while maintaining a gap for one piece of cell.
This is because a short circuit may occur if the gap decreases among the solar cells. However, if the gap is too great, the electric resistance increases among the solar cells. In addition, when a plurality of solar cells are connected together and assembled, the overall length may exceed a predetermined length, resulting in a defective product.
After assembly, the solar cell module is transferred from the conveyer to which the magnets are stuck to another conveyer so as to be fed to a next step (step of inspection, etc.). At this process, too, the solar cells must maintain the predetermined gap among themselves.
However, the following problems occur on the conveyer line that passes through the above-mentioned steps.
(1) The conveyer belts with magnets are obtained by sticking magnets to steel belts. As the steel belts stretch or bend at the pulley portions, the magnets crack, by a decrease of the durability, they peel off from the steel belts and their attractive forces decrease.(2) To replace the magnets, the entire conveyer belt must be replaced requiring laborious work. Therefore, the production line is forced to stop during the replacement.(3) The conveyer belts with magnets, which are steel belts, develop a very small degree of slipping relative to the pulleys, making it difficult to maintain the predetermined gap among the solar cells, and often resulting in defective products.(4) It is difficult to transfer the products from the conveyer belts with magnets to the next belt conveyer, and the products often become damaged.
The present invention was proposed in order to solve the above problems, and has an object of providing a solar cell module conveyer line which, in producing solar cell modules, intermittently positions and conveys a plurality of solar cells successively maintaining a predetermined distance enabling the products inspection and ejection.